التصوير الطبي و الأشعة التداخليه للمضاعفات الناتجة لمتبرع كبد حي

Imaging Findings and Interventional Management of Postoperative Complications of Living Related Donors in Liver Transplantation"

                                                "Transplantation is one of the greatest achievements of modern medicine with the integration of advances in immunosuppression and surgical techniques. Understanding the anatomy and pathophysiology of the liver and critical care of hepatic patients, all make liver transplantation a widely accepted therapy for patients with end-stage liver disease.

The persistent organ shortage and numerous deaths of patients on the waiting list for liver transplantation were the force for the introduction of living donor liver transplantation.

Living-donor liver transplantation (LDLT) was first initiated in children. Recently the indicators of LDLT have been extended to adults, especially in countries where the availability of brain-dead donors is severly restricted. The evolution of this modality has expanded its applicability to right lobe donations with good initial results.

The undisputed disadvantage of LDLT is the risk of serious complications or death in an otherwise healthy donor.

Although donor safety should be the top priorty in LDLT, accurate data on the donor morbidity and mortality and pre-operative evaluation of donors remain very scare.

Understanding the anatomy of the liver and the biliary system by using different imaging modalities is very valuable for pre-operative donor selection and detection of any clinical or surgical contraindications that would deny donors candidacy on the transplant list and also decreasing the frequency of post-operative complications.

The main objectives of pre-operative radiological evaluation include: assessment of the native liver size, any focal textural abnormalities and exclusion of vascular or biliary anomalies.

                Knowledge of the surgical technique of liver transplantation and awareness of the normal radiological appearance after that permit early detection of any intra- or post-operative complications.

Early post-operative routine imaging of the remaining part of liver and its vessels after liver transplantation is performed with gray-scale US and Doppler imaging, assures patency of the hepatic artery, portal vein, hepatic vein and IVC in addition to imaging of the biliary system.

Multidetector CT is a valuable complement to US (particularly for patients with inderterminate US results or in whom US examination is difficult) in the postoperative period. It is a safe, accurate, and non-invasive method of imaging the liver morphology, assessment of hepatic vessels, biliary dilatation, extra-hepatic tissues, fluid collections and infections. Also, used most commonly to guide percutaneous aspirations and abscess drainages.

MRI, MRA, MRV and MRCP can also be used to define the post-operative biliary tree and the hepatic vascular system.

The interventional radiologist plays a critical role in the treatment of postoperative donor complications. Percutaneous intervention has been strongly advocated and more recently accepted as the initial treatment for many transplant-related abnormalities.

Biliary complications are the most commonly reported donor morbidities. Percutaneous balloon dilatation in biliary stricture is used as a first line of treatment since it is less invasive compared to surgical alternative revision which is associated with even greater morbidity.

If recurrent stricture occurs after balloon dilatation, it should be treated by further dilatation and plastic stent placement or reconsidered for surgery. Metallic stents are only used as a last solution in patients with biliary stricture after liver transplantation.

Venoplasty is considered the treatment of choice for post-transplant portal venous stenosis which successfully dilates the stenosis and increases the hepatopedal flow, thus alleviating portal hypertension. Venoplasty may cause patency in the patients for up to five years. Stents are reserved for elastic portal venous stenoses or for recurrent lesions.

Percutaneous intervention can be successful in restoring venous patency. However, portal vein thrombosis is more difficult to treat. Some studies treated several patients with angioplasty, but associated morbidities may lead to death.

                Inferior vena caval complications are even occure but rarer than portal vein complications.

                Abnormal intra-abdominal fluid collection or pleural effusion may occure after liver donation. Percutaneous drianage under ultrasound or CT guidance is generally preferred over surgical techniques."